Valve member having conically tapered seating surface



V- 1963 c. L. GRIFFIN 3,409,039

VALVE MEMBER HAVING CONICALLY TAPERED SEATING SURFACE Original FiledJan. 6, 1958 (704/049 L. Gr/ff/n INVENTOR.

United States Patent M 16 Claims. (Cl. 137-516.29)

ABSTRACT OF THE DISCLOSURE Slush pump valve includes a seat ring havinga conically tapered seat with a rounded upper edge and a valve closureof sandwich type including a metal base plate at bottom and a metalpressure plate on top between which a rubber seal ring is retained underpressure. Outer periphery of base plate and lower part of outerperiphery of seal ring have same taper as seat. Upperpart of seal ringhas greater taper than seat and overlies rounded upper edge of seat andcontacts rounded edge initially on closure to cushion closure and wipesseat to insure a seal even on a dry seat.

This application is a continuation of my prior copending applicationSer. No. 74,068, filed Dec. 6, 1960, now abandoned, which was acontinuation of and copending with my original application Ser. No.707,219 filed Jan. 6, 1958, now abandoned.

This application pertains to valves and more particularly to valves forslush pumps such as are used in connection with oil well drilling.

According to the invention the pump body is provided at its inlets andoutlets with valve seat rings forming conically tapered seats with flowpassages axially therethrough. Each seat ring is rounded off slightly atthe upper edge of the conical seat. The valve member cooperating witheach seat ring includes a metal base plate having a tapered outerperiphery cor-relative to the valve seat, and on top of the base plateis disposed a ring of resilient sealing material whose outer peripheryistapered at the lower portion thereof correlative to the seat taper andin alignment with the taper of the base plate while the upper portionthereof tapers at a greater angle. When the valve closes the upperportion of the sealing material ring contacts the seat ring first anddeforms gradually to conform to the seat ring taper as the valve movesfarther down into the seat ring to come to rest with the base plate incontact with the scat ring.

This causes a gradual reduction of valve velocity as it closes andprevents the valve from being damaged by sudden impacts.

Also, the upper part of the sealing ring wipes the valve seat as thevalve closes, insuring a good seal even on a dry pump seat.

Since all the sealing and seating is done on one smooth continuousregularly shaped seating surface, and since the difference in taperangles between the upper and lower portions of the seal ring is notlarge, there is no disruption of the sealing ring at the juncture of thedifferently tapered portions thereof.

The construction is inexpensive to manufacture, repair, and maintain.

Other objects and advantages of the construction will become apparentfrom the following description of a preferred embodiment of theinvention wherein:

FIGURE 1 is a vertical axial section through a valve embodying theinvention showing same in open position, only the right hand half of thevalve being shown, and

3,409,039 Patented Nov. 5, 1968 FIGURE 2 is a similar view of the lefthand half of the valve showing same in closed position.

Referring now in both FIGURE 1 and FIGURE 2, the valve comprises a metalseat ring 10 having an axial flow passage therethrough. Three webs 12project radially inward from the flow passage wall to support a valvestem guide bearing 13 having an axial opening 14 therethrough. The outerperiphery 16 of the seat ring is tapered to facilitate its positioningin the pump body (not shown). The upper end of the valve seat ringaround the flow passage is tapered conically to provide an upwardlyflaring seat 17. The upper edge 18 of the seat is rounded.

The valve member cooperating with the valve seat ring comprises a metalbody having a guide stem 30. Stem 30 fits within the guide stem bearingand is provided with a plurality of rubber rings 31 set in annulargrooves therearound so as to be substantially flush with the outersurface of the stem. These rings reduce the rate of guide stem wear.

A base plate or flange 40 extends out from the valve body above theguide stem. The lower face of the base plate is fiat and lies in a planeperpendicular to the valve axis so as to overlie the tops of the Webs 12but not normally touch them. The outer periphery 41 of the base plateflares upwardly, being tapered conically correlative to the seat taper.The upper surface 42 of the base plate is conically tapered, convergingupwardly toward a cylindrical hub 43. There is an an annular rib 63projecting upwardly from the base plate.

The hub 43 terminates at a shoulder 44 where the body diameter reducesto provide a centering portion 45 for a top plate or pressure plate 46which is positioned therearound. A further reduced diameter portion 47midway of centering portion 45 forms an annular groove receiving Cshaped clamps 48 held together by snap ring 49.

At the upper end of the valve member is an upper valve stem 50 aroundwhich a biasing spring (not shown) may be placed and held in position bya fastening means (not shown) cooperating with annular groove 51. Heldbetween base plate 40 and pressure plate 46 is a seal ring 60 which hasa center opening 61 fitting around hub 43. The lower face 62 of the sealring is conically dished, i.e. tapered, converging upwardly, correlativeto the tapered upper surface of the base plate. An annular groove in thelower face 62; cooperates with rib 63 on the upper surface of the valveplate to provide interlocking means for retaining the seal ring on thebase plate against outward motion. The upper face of the seal ring isfiat, lying in a plane perpendicular to the valve axis. The relaxed.thickness of the seal ring is slightly greater than the space betweenthe pressure plate and base plate so as to place the seal ring underpressure when assembled so as to avoid any leakage past the hub.

The outer periphery of the seal ring includes a lower seating portion 70conically tapered at the same angle as the peripheral surface 41 of thebase plate and in line therewith to form a continuation of the conicalsurface thereof. A bulge at the juncture of the base plate and sealring, e.g. due to compression of the ring during assembly, is preferablyavoided, since such a bulge might contact the valve seat first. Thelower portion of the outer periphery of the seal ring, together with theouter periphery of the base plate, should be formed correlative to thevalve seat.

Adjacent and above the lower peripheral portion 70 of the seal ring isupper seating portion 71, which is also conically tapered, but at agreater acute angle to the valve axis than the lower seating portion.The difference in taper angles between the lower and upper seatingportions is preferably between 5 and 15 degrees, 10 degrees being a mostsuitable difference. Smaller differences in taper angle will reduce thewiping and cushioning effect of the uppenseating.portionwhile.largerdifferences in taper angle will place undue strain on the seal ring,tending to tear off the upper seating portion or will prevent the lowerseating portionv from engaging the valve seat at all. The portion of thesurface of seat ring lying directly below upper, seating portion .71 ishereinafter referred to as. the upper end face of the valve seat ring. v

Above the upper seating portion of the outer periphery of the seal'ring,there is a downwardly flaring portion 72 that is concave in verticalsection, providing increased flexibility to the outer tip 73 of the sealring formed between the 'upper seating portion of the oute'r'peripheryand the lower part of the concave flaring portion, The flaring portion72 preferably makes an angle'of from zero to degrees with the horizontalplane 'at its juncture with upper seating portion 71, an angleof 15degrees being most suitable. With a preferred seat taper angle ofdegrees relative to the axis of the seat ring and the most suitableangles for the upper'and lower s urfaces of the tip of the seal ring,the included angle of the tipwould be degrees. A seat taper angle in therange of 25 to 55 degrees ismost suitable.

With a seat taper angle at the large end of the preferred range, i.e.,55 degrees and a difference of taper angles between the upper seatingportions also at the large end of the preferred range, i.e. 15 degrees,the taper angle of the upper seating portion will be seventy degrees. Itis thus apparent that the preferred taper angle of the upper seatingportion is less than 71 degrees.

It is to be noted that the pressure plate has substantially the sameouter diameter as the base plate so that in vertical section the tipforms the apex of a triangle whose base line connects the outerperipheries of the pressure plate and base plate.

The angle of the tip forming the apex of the triangle is preferably inthe range of 45 to 90 degrees. This construction provides flexibilitywithout such weakness as to make the tip subject to tearing. It isimportant that the tip have some flexibility in order to allow fordisplacement of the seal ring material as the valve seats withoutnecessitating too much flow of material which would cause bulging andundue strain at the concave flaring surface of the seal ring, this beingthe only unsupported surface toward which any flow can take place, forthe seal ring is preferably made of a compound of some oil and waterresistant natural or synthetic rubber compound having a durometerhardness in the range of to 90, a hardness of being more suitable, andsuch a material is substantially incompressible and can only flow orflex to allow for reduction of space available.

- In operation when the valve closes the lower surface of tip 73 willseat first against rounded edge 18 of the seat ring causing the tip toflex upwardly. The flexure of the tip will continue as thevalve closesuntil the lower surface 71 of the tip is aligned with the valve seat.During this period the tip wipes the valve seat to insure an immediateseal, at the same time cushioning the valve member so as to reduce theimpact on final seating, thereby prolonging valve life. The tip alsowipes the seat during opening of the valve.

It may be added that during the life of the valve the seat may .wearaway adjacent the metal base plate, permitting the valve to movefurther, down. This motion is ultimately limited by the base platecontacting the tops of the webs 12. The seal ring should be replacedbefore this occurs, but such limitation limits the degree of distortionto which the seal ring, or valve insert as it is usually known, issubjected. The grooves 74 across the topsof the webs 12 at theirjunctures with the valve seat provide for ease in machining and alsoserve as trash receptors to prevent sand or the like washed down fromthe valve seat during the wiping action from building up on the webs tosuch a degree as to prevent closure.

Whenever the seal ring becomes unduly worn, it can of course be easilyreplaced by removing the snap ring and C clamps and pressure plate. Whena new seal ring is .putonan old worn valve body, itmay extend out beyondthe line of the tapered portion of the base plate.

While a preferred embodiment of the invention has been shown anddescribed, many modifications thereof can be made by. one skilled theart without departing from the spirit of the invention and it,isintended to cover by Letters Patent all formspf the invention fallingwithin the-scope of the following claims: a

I claim: f t I 'Avalve insert'comprisinga ring, of resilient-sealingmaterial having a" lower peripheral tapered seating surface and an upperperipheral "tapered seating surface whose taper angle is, greater thanthat of said lower seating surface, said ring being adapted forcooperation with a conically tapered metal valve seat having the sametaper angle as said.lo ,wer seating. portion, said ring being made ofelastor'neric material having a durometer hardness in the range of-65-90, said seating surfaces being conical with straight linecross-sections, said ring being adapted for disposition between a metalbase plate therebe'low having a conically tapered outerperiphery and ametal top plate thereabove, said ring including a portion extendlngabove the upper edge ofsaid upper sealing portion for engagement withsuchupper plate.

.2. The combination of claim 1 in whichthe difference in. taper angleslies in the range of flve degrees to fifteen degrees, and the upperseating surface makes an angle with the ring axis of less than 71degrees.

3. The combination of claim 1 in which the difference in taper angles issubstantially ten degrees.

,4, The'combination of claim 1 in which the seal ring has a downwardlyflaring surface above and adjacent said upper seating surface andforming therebetween an annular tip.

5. The combination of claim 4 in which the interior angle of the tip isin the range of forty-five to ninety degrees.

6. The combination of claim 4 in which the interior angle of the tip issubstantially sixty degrees andthe downwardly flaring surface is concavein vertical section.

7. A valve comprising a seat ring having a conically tapered seat, anda'valve member cooperable therewith including a base plate, a pressureplate; and a seal ring therebetween, said seal ring being composed ofrubber compound having a durometer hardness in the range of 65 to 90,said base plate having a peripheral seating portion tapered correlativeto said seat, said seal ring having a lower peripheral tapered seatingportion forming a continuation of said seat portion ofthe base plate,said seal ring having an upper tapered seating portion adjacent andabove said lower seating portion and having a greater taper angle thanthe seat, the upper edge of said seat being rounded, said upper seatingportion of the seal ring overlying said rounded edge, said seat taperangle relative to the seat axis lying in the range of 25 to 45 degrees,the difference in taper angles of said upper and lower seatingportionsof the seal ring being in the range of 5 to 15 degrees, saidseal ring having a downwardly flaring surface above and adjacent'saidupper seating portion forming an annular flexible tip therebetween, theinterior angle of said tip being in the range of 45 to degrees, saiddownwardly flaring surface being concave in vertical section. v

8. 1A seal ring adapted for use with a valve including a seat ringhaving a conically tapered seat and a valve member cooperable therewithadapted to carry the seal ring with its outer periphery in position .toengage the seat,

said seal ring being made of elastomeric material having a durometerhardness in the range of 65-90, said seal ring outer periphery having alower conically tapered seating surface having a straight line crosssection adapted to engage a correlatively tapered seat ring seat,characterized by the fact that said seal ring includes:

a conically tapered seating surface at its upper periphery adjoiningsaid lower seating surface,

said upper seating surface having a straight line cross section,

said conically tapered upper seating surface having a greater taperangle relative to the axis of the ring than said lower seating surface,

an upwardly converging surface above and adjacent said upper seatingsurface forming therebetween an annular tip having an included anglebetween 45 and 90 degrees,

the difference in taper angle between said upper and lower seatingsurfaces being in the range of five degrees to fifteen degreesfacilitating flow of said upper seating surface into alignment with saidlower seating surface to engage the same conically tapered seat.

9. A seal ring adapted for use with a valve including a seat ring havinga conically tapered seat and a valve member cooperable therewith adaptedto carry the seal ring with its outer periphery in position to engagethe seat,

said seal ring being made of elastomeric material having a durometerhardness in the range of 65-90, said seal ring outer periphery having alower conically tapered seating surface having a straight line crosssection adapted to engage a correlatively tapered seat ring seat,characterized by the fact that said seal ring includes:

a conically tapered seating surface at its upper periphery adjoiningsaid lower seating surface, said upper seating surface having a straightline cross section, all lines passing through the axis of said ring thatare tangent to the surface of the portion of said ring immediately aboveand adjacent to said upper seating surface will pass through a portionof said elastomeric material, said conically tapered upper seatingsurface having a greater taper angle relative to the axis of the ringthan said lower seating surface, the difference in taper angle betweensaid upper and lower seating surfaces being in the range of five degreesto fifteen degrees facilitating flexure of said upper seating surfaceinto alignment with said lower seating surface to engage the sameconically tapered seat, said conically tapered upper seating surfacehaving a taper angle less than 71 degrees relative to the axis of thering, 7 whereby said conically tapered upper seating surface is adaptedto make the initial valve closing contact with the seat of a seat ringhaving a conically tapered seat.

10. A valve closure comprising a metal base plate having an upwardlyflaring conical outer periphery,

an elastomeric annular valve insert on top of said plate, a metal topplate on top of said insert, the lower portion of said insert adjacentsaid base plate having a conically tapered outer periphery having thesame taper angle as said base plate outer periphthe riddle portion ofsaid insert adjacent said lower portion having a conically tapered outerperiphery of somewhat greater taper angle than said outer periphery ofsaid lower portion,

the upper portion of said insert between said top plate and said middleportion being of less diameter of said middle portion and providing abody into which the elastomeric material of the middle portion can flowto allow the outer periphery of the middle portion to contract to thesame taper angle as the outer periphery of the lower portion.

11. In combination, a pump valve element and a seat element each ofrigid material and each having a pressure end and said elementsincludingmutually-mating frustoconical seating faces tapering withincreasing diameter toward the pressure end of each element, one of saidelements having an annular groove adjacent its seating face and oppositethe seating face of the other element and located near its pressure endwhen said faces are engaged; a sealing member of resilient materialfilling said groove flush with the associated face and having an annularbead extending therebeyond toward the seating face of the other element,the other element including a transverse surface at its pressure end andthe bead including enough resilient material that when deformed by themating of said faces the material will extrude out and partly overliethe transverse surface of said other element.

12. In the combination set forth in claim 11, the valve element having atransverse pressure faceat its pressure end and said annulargroove beinglocated between its seating face and its pressure face; and saidresilient sealing member having a transverse portion at least partlyoverlying said pressure face.

13. In the combination set forth in claim 12, a ring of rigid materialoverlying at least part of said transverse portion of the sealingmember; and securing means fixing the ring to the body at the pressureface thereof.

14. In the combination set forth in claim 11, said resilient sealingmember comprising rubber-like material secured to the surface of theassociated member.

15. A valve comprising a metal seat ring having a conically tapered seatand a valve member cooperable with said seat ring including a metal baseplate having an outer peripheral conically tapered seating surfacecorrelative to the lower portion of said seat, the taper of said seatingsurface being the same as that of said seat, said valve member furtherincluding a seal ring mounted on said base plate, said seal ring beingmade of elastomeric material, said seal ring having a lower conicallytapered seating portion adjacent to and overlying a medial portion ofsaid conically tapered seat and an upper conically tapered seatingportion adjacent to and overlying the upper part of said conicallytapered seat, said upper seating portion having a greater taper anglerelative to the axis of the seal ring than said lower seating portion,the difference in taper angle between said upper and lower seatingportions being in the range of five to fifteen degrees,

the improvement according to which said upper seating portion projectsradially outwardly beyond the cone defined by the geometrical projectionof said tapered seating surface of the base plate whereby said upperseating portion contacts said seat prior to contact thereof by saidlower seating portion of said seal ring and by said seating surface of=said base plate upon downward travel of said valve member coaxial withsaid seat,

the portion of said seal ring overlying said upper seating portion beingfree to flex upwardly upon contact of said upper seating portion withsaid seat to conform the taper angle of said upper seating portion withthat of said seat and said seating surface of the base plate wherebysaid seating surface of said base plate can then move into engagementwith said seat upon continuation of said downward travel of said valvemember, said lower seating portion having the same taper angle as saidseating surface of said base plate and said seat, no part of said lowerseating portion lying inside the cone defined by the geometricalcontinuation of said conical seating surface of said base plate, wherebysaid lower seating portion moves into engagement with said seat no laterthan the time of engagement of said seat by said seating surface of saidbase plate.

16. A valve comprising a metal ring having a conically tapered seat andan upper end face, a valve member cooperable with said seat ringincluding a seal ring,

said seal ring being made ofelastorneric material, said seal ring havinga lower peripheral conically tapered seating portion adjacent a portionof said conically tapered seat for engagement therewith and correlativethereto, said lower seating portion having the same taper angle as saidseat, characterized by the fact that said seal ring includes:

a conically tapered upper peripheral seating portion adjoining saidlower seating portion, said upper seating portion overlying said upperend face for engagement with said upper end face, said conically taperedupper seating portion having a greater taper angle relative to the axisof the seal ring than said lower seating portion, the taper angle ofsaid upper seating portion being no greater than 70 degrees leaving atleast a ZOdegree angle between said upper seating portion an'dahorizontal plane perpendicular to the axis of the seat ring,

the difference 'in taper angle between said upper seating portion andsaid lower seating portion being less than said angle between'said upperseating portion and said horizontal plane.

I, Reiernceis'Cited UNITED STATES PATENTS f 12/ 1908 Great Britain.

4/1950 Australia.

ARNOLD ROSENTHAL, Primary Examiner.

